This invention relates to coupling systems for one transfer of materials from one unit to another, and, more particularly, to coupling units with a first unit including a a swabbable access port and a second unit including a blunt cannula. The access port receives the blunt cannula to effect a coupling of particular medicinal applicability for medications and body fluids. The swabbability of the access port allows disinfectant treatment before receipt of the blunt cannula to limit the extent to which pathogens can enter the cannula after coupling is effected.
In medical practice, containers for medication typically are bottles capped with rubber-like stoppers. A tamper-evident seal surrounds the stopper and at least the upper portion of the container. To administer medication, the seal is removed, a syringe with a needle or cannula is used to puncture the rubber stopper and withdraw a proper dosage for aministration to a patient.
The need for a needle or cannula presents a potential hazard, both to medical personnel and to the patient. There is significant risk of infection by blood-transmitted diseases, AIDS and hepatitis from needle sticks.
Accordingly, it is an object of the invention to reduce the hazards associated with the administration of medication. A related object is to reduce the hazards associated with removal of medication from sealed containers.
In additional to medicinal containers, pointed needles or annulae have been widely used in conjuction with other forms of access ports, which take the form of a septum or piercable membrane. An illustrative access port that is used with a piercing cannula is disclosed in Zdeb U.S. Pat. No. 4,412,573 xe2x80x9cInjection Sitexe2x80x9d assigned to Baxter International Inc. of Deerfield, Ill.
The pointed cannula can be forced through the septum in order to establish fluid communication between the cannula and the container housing a medicinal substance. Access ports that are pierced by a cannula can be physically damaged by repetitive piercings and produce coring or laceration of the access port, which can result in leakage.
For standard drug vials, the access ports take the form of rubber stoppers which are routinely entered using conventional hypodermic needles. In order to maintain sterility, the stopper is swabbed with a disinfectant before there is a needle entry. After repeated entries, the stopper can leak because of coring and no longer function as a swabbable sterile barrier.
In addition to pathogens which may become present in the pierced sites, particulate matter can be generated and injected into a patient, along with pathogens. Alternatively, the pathogens and particulate matter may contaminate the contents of the vial. These conditions are pronounced with vials that are accessed multiple times.
Moreover, pointed cannulae used with drug vials pose a health risk to their users because of problems associated with infectious agents. Despite the fact that personnel using pointed cannulae do so with great care, from time to time accidents occur, and the users are jabbed or suffer needle sticks.
In an attempt to overcome difficulties associated with the use of pointed cannulae, xe2x80x9cdispensing pinsxe2x80x9d can be used to penetrate the site or stopper of multiple dose vials. A dispensing pin typically takes the shape of a sharp spike and can be used with a check valve to limit fluid leakage. One end of the spike has standard luer fitment that is typically closed off, when not in use, by a cap. Dispensing pins tend to disengage from the vial stopper with resultant leakage. Further, it is difficult to maintain sterile conditions on this kind of multiple dose system.
One attempted solution has been to eliminate sharp cannulae and use blunt cannulae instead. An example is Garrett et al. U.S. Pat. No. 4,197,848 xe2x80x9cClosed Urinary Irrigation Sitexe2x80x9d, assigned to Baxter International. In Garrett the injection site is a relatively low pressure device with a relatively thin, molded sealing member that has an opening which permits a blunt cannula to be forced through the sealing member into fluid communication with the interior of the injection site.
Injection sites used with a blunt cannula have the advantage that the cannula will not pierce the skin of a user, but the pre-slit injection site has to reseal with enough force that fluids do not ooze outwardly and not allow airborne particulate matter, bacterial or viral, to enter.
Hence, there continues to be a need for an injection site which can be used with a variety of solutions and over a range of fluid pressures. Further, there continues to be a need for such an injection site which will reliably reseal even after many insertions of a blunt cannula.
If intended to be reusable, the injection site should be able to receive a large number of insertions of the cannula without displaying reseal failure. Such an injection site should provide for alignment of the cannula on insertion to result in less chance of damage to the injection site after repeated insertions. In addition, although pointed cannulae desirably are to be avoided, in some situations they may be the only ones available, so that the injection site also should be usable with pointed cannulae.
Further, the injection site should be usable with a blunt cannula with a reasonable level of insertion force that will permit health care personnel to readily insert the cannula, but yet not have the cannula easily displaced after insertion.
One attempt to meet these objectives is disclosed in Dudar et al. U.S. Ser. No. 425,790 (Oct. 23,1989) xe2x80x9cPre-Slit Injection Sitexe2x80x9d in which one end of a housing carries a pre-slit septum, and a second end has a coupling to adapt the housing to standard vials. The coupling or a vial adapter includes a spike with openings that allow drainage of fluid in the vial through the spike and into the injection site. The vial adapter has a skirt which protects the adapter spike in both manufacture and use. The skirt also permit locking engagement of the adapter with injection site to standard vials, despite dimensional variations in vial closures. The coupling spike can having a barb that can be inserted into a standard vial and resist disengagement. A blunt cannula is used with the combination of the injection site with the coupling. This system is both complex and cumbersome.
Accordingly it is a further object of the invention to achieve the foregoing advantages without the need for a pre-slit injection site.
In accomplishing the foregoing and related objectives, the invention provides for a swabbable access port formed by a stopper having a bore extending from an entry position to an exit position; and a swabbable plug in the bore at the entry position and movable in the bore.
In accordance with one aspect of the invention the swabbable plug extends integrally across the bore and can be frangibly connected to the bore, or be slidably connected to the bore.
In accordance with another aspect of the invention the swabbable plug has a non-planar external surface and is pierceable by a cannula. The stopper can have a collar at the entry position, and the collar can have external Luer threads.
A stretchable and apertured membrane can span the exit position of the bore so that when the plug is depressed into the bore by, for example, the end of a fitment, the plug can be restored to its original, swabbable position at the entry position of the stopper when the fitment is removed.
In accordance with a method of the invention for accessing a port, the steps include (a) swabbing a movable plug positioned in the bore of a stopper, for which the bore extends from an entry position, where the plug is swabbed, to an exit position; and (b) moving the plug within the bore away from the entry position; whereby communication can be established along the bore between the entry position and the exit position.
The method further includes the step of swabbing an integral surface of the movable plug, with the surface extending integrally across the bore. The swabbing can take place with respect to frangible connections to the bore.
In one aspect of the method, further steps include slidably moving the plug along the bore; engaging the plug by a fitment with a transverse gap between a portion of the exterior surface of the plug and the engagement end of the fitment; and piercing the plug by a cannula.
In another aspect of the method the steps include engaging a collar of the stopper at the entry position of the bore; engaging external Luer threads of the collar; sretching an apertured membrane that spans the exit position of the bore; and causing fluid to flow in an auxiliary channel of the bore when the plug is depressed in the bore.
A system of the invention for the transfer of medication from a container includes (a) a needleless syringe having a blunt tubular end; (b) a stopper positioned in a neck portion of the container and having a central throughbore extending from an outer surface of the stopper to the interior of the container; (c) a plug extending into the bore from the outer surface of the stopper; (d) protrusions on the plug for engagement by the end of the syringe permitting fluid flow between the syringe and the plug; and (e) an auxiliary channel in the bore permitting the fluid flow to extend between the container and the syringe.
The invention enables the needleless and disinfected transfer of medication using a stopper with a movable plug having an integral surface for engagement of the plug by a fitment, such as the Luer end of a syringe. By using the invention, medication can be withdrawn from a container with or without the use of a needle, after disinfectant treatment of the engagement surface of the plug to remove pathogens and possible contaminants.